Diabetes in the United States today is an explosive major public health issue that directly impacts cardiovascular morbidity and mortality. One major reason for these devastating cardiovascular complications is that diabetics exhibit impaired collateral vessel development. Formation of functional collateral blood vessels is the primary adaptive mechanism in humans to blood flow obstruction. In this project we will explore the role of advanced glycation end products and the specific receptor for advanced glycation end products (RAGE) in inhibition of collateral blood vessel formation. We have developed exciting preliminary data showing that advanced glycation end products dramatically inhibit collateral vessel formation. Moreover, we have presented preliminary data that demonstrate a central role for RAGE signaling in monocytes in this process. The proposed studies will first examine the overall role of RAGE in inhibiting collateral vessel formation. Subsequent aims will study the specific contributions of RAGE in monocytes and T cells as these two inflammatory cells types have been shown by us and others to be critical for the formation of collateral blood vessels. Additional studies will examine the role of reactive oxygen species as crucial signaling intermediates in RAGE signal transduction in both monocytes and T cells. Through these studies, we will develop a comprehensive and critical assessment of the role of RAGE signaling in inflammatory cells and the subsequent impact on collateral vessel formation.